Controlling displays for processor-based systems

ABSTRACT

A processor-based system may include a display and a sensor which detects the orientation of the display with respect to the rest of the system. As the system is displaced, the sensor detects the orientation of the system. The system may automatically alter a characteristic of information displayed on the display in response to the detection of a change in orientation.

BACKGROUND

[0001] This invention relates generally to processor-based systems andto controlling the display of information on displays associated withprocessor-based systems.

[0002] A variety of processor-based systems include a housing and adisplay coupled to the housing. For example, a conventional laptopcomputer includes a housing having a keyboard and a display screen whichmay be, for example, a liquid crystal display. The orientation of thedisplay with respect to the housing may be adjustable through a hingeconnection between the display and the housing.

[0003] A variety of hand-held devices including personal digitalassistants (PDAs) may also have displays. Many hand-held or portabledevices are usable in a variety of different orientations. In manycases, the displays may be rectangular so that some information may bedisplayed along the length direction of the screen and other informationmay be displayed along the width direction.

[0004] However, generally, displays work in only one direction. That is,information is always displayed in the same orientation, normally drivenby software, regardless of the display's orientation. As a result, insome cases, the display of information may be unsuitable for theorientation of the display. For example, the angulation of the displaywith respect to the user may make it difficult to view material on thedisplay. In addition, the user can not readily control the orientationof information set forth on the display.

[0005] Thus, there is a continuing need for better ways to controldisplays used in processor-based systems.

SUMMARY

[0006] In accordance with one aspect, a method of displaying informationon a processor-based system includes detecting the orientation of thedisplay coupled to the system. A characteristic of the informationdisplayed on the display is changed in response to the detectedorientation of the display.

[0007] Other aspects are set forth in the accompanying detaileddescription and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008]FIG. 1 is a perspective view of one embodiment of the presentinvention in a first orientation;

[0009]FIG. 2 is a perspective view of the embodiment shown in FIG. 1 ina different orientation;

[0010]FIG. 3 is a perspective view of the display of FIG. 1 in stillanother orientation;

[0011]FIG. 4 is an enlarged, side elevational view of the display shownin FIG. 1;

[0012]FIG. 5 is a schematic or block depiction for one embodiment forimplementing the display shown in FIG. 1;

[0013]FIG. 6 is a block diagram for implementing the accelerometer shownin FIG. 5; and

[0014]FIG. 7 is a flow chart for one embodiment of software forimplementing the embodiment shown in FIG. 1.

DETAILED DESCRIPTION

[0015] A processor-based system 10 may include a housing 14 coupled to adisplay 12, as shown in FIG. 1. The display 12 may be coupled by a hinge15 to the housing 14. The housing 14 may conventionally include akeyboard 13 in one embodiment of the present invention.

[0016] While the present invention is illustrated in a format commonlyassociated with personal digital assistants (PDAs), the presentinvention is applicable to a variety of other embodiments. In someembodiments of the present invention, the system may be a portableprocessor-based system which is operated by battery power. In addition,in some embodiments of the present invention, the processor-based system10 may be hand-held as illustrated in FIG. 1.

[0017] The display 12 may be arranged in a rectangular format having alonger axis X and a shorter axis Y. In the embodiment shown in FIG. 1,the displayed information extends from left to right along the X axisand up and down in Y axis. Thus, the upper edge 11 of the display 12corresponds to the top of the textual material.

[0018] Referring to FIG. 2, the display 10 has been rotatedapproximately 90°. The housing 14 and the display 12 have been rotatedto the right. Now the display 12 has a more upright configuration.Information displayed on the display 12 now uses the side edge 17 as theupper edge for purposes of displaying text. In other words, the textualinformation now extends up and down in the X axis and the across in theY axis using the convention set forth in connection with FIG. 1.

[0019] Thus, in one embodiment of the invention, the system 10automatically changes the orientation of the displayed information inresponse to the detection of tilting or orientation of the system 10.These changes maybe implemented automatically in response to thedetection of rotation of approximately 90° of the housing 10. Thus, ifthe user wishes to rotate the way information is displayed on thedisplay 12, the user can do so by simply rotating the entire system 10from the orientation shown in FIG. 1 to the orientation shown in FIG. 2.

[0020] While the embodiment shown in FIG. 2 may be convenient for aleft-handed or a right-handed person, the system 10 can be rotated 180°from the configuration shown in FIG. 2 to the configuration shown inFIG. 3. As a result, the text displayed on the display 12 may besimilarly rotated through 180° so that the upper edge of the text is nowaligned with the edge 19 of the display 12, in one embodiment of theinvention. Again, the transpositioning of the text on the display 12 maybe implemented automatically in response to detection of the rotation ofthe system 10 from the orientation shown in FIG. 2 to anotherorientation.

[0021] Referring now to FIG. 4, the system may also detect the rotationof the display 12 with respect to the housing 14 around the hinge 15. Asthe display 12 rotates, as indicated by the angle A, the orientation ofthe characters on the display may be changed so that regardless of theorientation of the display, a fixed user still sees letters insubstantially the same orientation. Thus, the aspect ratio ofinformation displayed on the display may be altered, for example bymaking the letters taller or shorter. Thus text may have the sameappearance with respect to a fixed point of view regardless of the anglethrough which the display 12 is rotated relative to the housing 14.

[0022] In each of the instances described above, a characteristic of thedisplay is altered in response to a change in orientation of the system10. The characteristic that may be changed may include, among otherthings, the orientation of textual material on the display, the aspectratio of characters displayed on the display and how information on thedisplay may be actuated, for example, in response to a mouse-type cursorcontrol system. In addition, other characteristics may also be modifiedin response to orientation changes.

[0023] In another embodiment of the present invention, the detectedorientation of the display may be used to improve the display quality.For example, at some orientations of the display with respect to theuser, the display may be washed out or may be subject to contrastreversal. In such cases, by recognizing the orientation of the displaywith respect to the user, the system may adjust the contrast based onthe display orientation. This may help to ameliorate contrast reversalor wash out. In some embodiments of the present invention, the displayand associated processor-based system may be able to deduce theorientation of the user with respect to the display. For example, theway the user moves the display to improve the view of the display maygive information about where the user's eyes are positioned with respectto the display. This information may be useful in overcoming contrastreversal or wash out and may assist in adjusting the contrast to improvethe quality of the display.

[0024] In some embodiments, the function of the various keys 21 makingup the keyboard 13 may also be altered in response to orientationchanges. That is, a given key may signify different input commands indifferent orientations of the system 10 with respect to a presetorientation, such as the one depicted in FIG. 1. In other words, theassignments of key functions may be altered in response to detection ofthe orientation of the system 10 with respect to gravity.

[0025] In still another embodiment of the present invention, thereorientation of the system 10 may be recognized as a software triggeror input command. For example, in response to the change of the system10 from the orientation shown in FIG. 1 to that shown in FIG. 2, thesystem may automatically switch from running an e-mail program torunning a calendar or scheduling program. In such case, the change inorientation automatically selects a different application program to runon the system 10. In some cases, a particular application program may beassociated with a given orientation. In some embodiments, a givenapplication may be better suited to displaying information in oneorientation and thus the application may be invoked whenever the system10 assumes that orientation. In other cases the orientation is merely anarbitrary software trigger.

[0026] In addition, the orientation change may provide an input signalto select a given feature in an application program already running, asanother example. For example, a given rotation of the display may berecognized as accepting or answering “yes” to an option offered bysoftware running on the system 10.

[0027] Referring next to FIG. 5, the system 10, within the housing 14,may include a processor 16 coupled to an interface 18. The interface 18,for example, may be a chipset or a bridge. The interface 18 may couple abus 24, a system memory 20, and a display controller 22. The displaycontroller 22 may in turn be coupled to the display 12.

[0028] The bus 24 may be coupled through an interface 30 to aaccelerometer 32. In some embodiments of the present invention, theaccelerometer 32 may be a solid state accelerometer which measuresacceleration along at least two transverse axes. In other embodiments ofthe present invention, the accelerometer 32 may measure gravitationalcomponents along three transverse axes. In some cases, two or moreaccelerometers, oriented at an angle with respect to one another, may beutilized. The interface 30 is responsible for receiving informationabout the display's orientation and converting it to a format usable bysoftware operating on the system 10.

[0029] A serial input/output (SIO) device 34 may be coupled to thekeyboard 13. A storage device 26 may store software 36 for operating thesystem 10. The device 26 may store the software 36 for changing acharacteristic of the display in response to the detected orientation ofthe system 10. Conventionally, the system may also store other softwaresuch as an operating system and application software. The storage 26 mayconventionally be a hard disk drive or, in connection with batterypowered or portable systems, the storage 26 may be implemented in wholeor in part by a flash memory. A basic input/output system (BIOS) may bestored in a memory 28 also coupled to the bus 24. While one embodimentof hardware for implementing the present invention is illustrated inFIG. 5, those skilled in the art will appreciate numerous othervariations.

[0030] The accelerometer 32 may be implemented, in one embodiment of thepresent invention, by a single chip solid state device. A three axissolid state accelerometer 32, illustrated in FIG. 6, includes an X axissensor 38 a, a Y axis sensor 38 b, and a Z axis sensor 38 c. Thus, eachsensor 38 measures acceleration in one of three transverse axes. Eachsensor output signal is modulated by a clock signal 52 which also drivesthe demodulators 50 a, 50 b and 50 c. The output signal of each sensor38 a, 38 b or 38 c is amplified by a gain amplifier 40 a, 40 b or 40 c.

[0031] Each demodulated signal is adjusted by a buffer amplifier 56 a,56 b and 56 c. One input port of each buffer amplifier 56 is connectedto a trimming or offset network which may be a resistor network. Thenetwork provides an offset or adjustment signal for each axis X, Y or Z.

[0032] The circuit 34 may use a commercially available two axis solidstate accelerometer such as the ADXL250 available from Analog Devices,Norwood, Mass. 02062 and a transversely mounted single axisaccelerometer such as the ADXL150 also available from Analog Devices.Other devices of this type are available from other manufacturers.

[0033] The circuit 34 may provide an X, Y and Z axis acceleration outputwhich may be converted into a digital format by an analog to digitalconverters 36 a, 36 b or 36. A suitable analog to digital converter is a10 bit converter such as the AD7810 also available from Analog Devices.Additional filtering may be provided to eliminate jitter. The ADXL250and ADXL150 accelerometers may be programmed to sense a givenorientation as a null position relative to gravity and thereafter todetect orientation changes along one or more of three axes.

[0034] Each acceleration sensors 38 may be a micromachined sensorelement made by depositing polysilicon on a sacrificial layer that isthen etched away leaving a suspended sensor beam. A differentialcapacitor sensor may be composed of fixed plates and moving platesattached to the beam that moves in response to acceleration. Movement ofthe beam changes the differential capacitance which is measured by thecircuit 34.

[0035] Referring now to FIG. 7, the software 36 for changing acharacteristic of the display in response to the orientation of thesystem 10 begins by receiving an acceleration signal, as indicated inblock 54. Conventionally, the accelerometer signal may provideinformation about an acceleration in one of at least two transverseaxes. That signal may be converted into orientation information asindicated in block 56.

[0036] In some cases it may be desirable to have a time out orintegration function. This avoids software changes in response tomomentary or inadvertent orientation changes. Thus, the time outfunction illustrated in block 55 determines if the orientation changepersisted for a sufficient period of time (for example, a half second)to indicate the operator's intent to provide a software input in theform of an orientation change. In other cases, the time out function mayalso operate as a filter to eliminate obviously incorrect information.For example, relatively persistent vibrations may be interpreted asbeing indicative of in car operation and may be discarded. Similarly,periodic handshaking of relatively small amplitude may also berecognized and may be discounted. While in the illustrated embodiment,this time out feature is accomplished in software, those skilled in theart will appreciate that the same type of operation may be done inhardware using timers or hardware integrators.

[0037] In many cases, the precise orientation of the display relative togravity is not important. Instead, it is sufficient to know whether thedisplay is generally oriented in, for example, one of the positionsshown in FIGS. 1, 2 and 3. Thus, information from the accelerometer 32may be compared to information in a look up table to determine which ofthe three preset orientations most closely corresponds to the actualinformation provided by the accelerometer 32.

[0038] Once an orientation is determined, a characteristic of thedisplay may be adjusted (block 58). For example, the informationdisplayed on the display may be rotated to orient that information alongthe length of the display or along its width, as the case may be.Alternatively, the aspect ratio of letters displayed on the screen maybe increased or decreased in response to the angle of the display 12relative to the housing 14. In addition, the orientation of theinformation on the display may be changed to either a left-handed orright-handed orientation as indicated in FIGS. 2 and 3. Othercharacteristics may be changed as well. In addition, the detection of adisplay transposition may provide a user input to control or select theoperation of software on the system 10.

[0039] While the present invention has been described with respect to alimited number of embodiments, those skilled in the art will appreciatenumerous modifications and variations therefrom. It is intended that theappended claims cover all such modifications and variations as fallwithin the true spirit and scope of this present invention.

What is claimed is:
 1. A method of displaying information on aprocessor-based system comprising: detecting the orientation of adisplay coupled to said system; and changing a characteristic of theinformation displayed on said display in response to the detectedorientation of the display.
 2. The method of claim 1 further includingdetecting the angle of the display with respect to the rest of theprocessor-based system and changing the aspect ratio of charactersdisplayed on the display in response to the detected orientation of thedisplay.
 3. The method of claim 1 wherein changing a characteristicincludes changing the orientation of information displayed on saiddisplay.
 4. The method of claim 3 including rotating the informationdisplayed on the display approximately 90° in response to a displacementof said display of approximately 90°.
 5. The method of claim 3 includingrotating the information displayed on said display by a approximately180° in response to a displacement of said display of approximately180°.
 6. The method of claim 1 wherein changing a characteristicincludes automatically changing said characteristic in response to thedetection of the orientation of said display.
 7. The method of claim 1wherein changing a characteristic includes selecting a program foroperation based on the orientation of the display.
 8. The method ofclaim 1 wherein changing a characteristic includes utilizing displayorientation as a software input command.
 9. An article comprising amedium for storing instructions that cause a processor-based system to:detect the orientation of a display coupled to said system; and change acharacteristic of the information displayed on the display in responseto the detected orientation of the display.
 10. The article of claim 9further storing instructions that cause a processor-based system todetect the angle of the display with respect to the rest of theprocessor-based system and change the aspect ratio of letters displayedon the display in response to detected orientation of the display. 11.The article of claim 9 further storing instructions that cause aprocessor-based system to change the orientation of informationdisplayed on the display.
 12. The article of claim 11 further storinginstructions that cause a processor-based system to rotate theinformation displayed on the display by approximately 90° in response toa displacement of the display of approximately 90°.
 13. The article ofclaim 11 further storing instructions that cause a processor-basedsystem to rotate the information displayed on the display byapproximately 180° in response to a displacement of the display ofapproximately 180°.
 14. The article of claim 9 further storinginstructions that cause a processor-based system to automatically changea characteristic in response to the detection of the orientation of thedisplay.
 15. The article of claim 9 further storing instructions thatcause a processor-based system to select a program for operation basedon the orientation of the display.
 16. The article of claim 9 furtherstoring instructions that cause a processor-based system to use a signalindicative of the orientation of a display as a software input command.17. A processor-based system comprising: a processor; storage coupled tosaid processor; a circuit that produces a signal indicative of theorientation of the circuit, said circuit coupled to said processor; andsoftware stored on said storage to cause information to be displayed indifferent formats depending on the orientation of said circuit.
 18. Thesystem of claim 17 wherein said circuit includes an accelerometer. 19.The system of claim 18 wherein said accelerometer senses accelerationsin at least two transverse axes.
 20. The system of claim 19 wherein saidaccelerometer senses accelerations along at least three transverse axes.21. The system of claim 17 further including a display and a housingincluding a keyboard, said housing hingedly connected to said display.22. The system of claim 21 wherein said display has a longer and ashorter axis, and said software changes the way information is displayedbetween a first orientation where information is displayed along thelonger axis and a second orientation which information is displayedalong the shorter axis.
 23. The system of claim 22 wherein informationis displayed in one of at least two orientations along the longer axis,each orientation inverted with respect the other.
 24. The system ofclaim 21 wherein said software changes the aspect ratio of informationdisplayed on said display based on the angle of said display withrespect to said housing.